Why do chatbots suck?

Faisal Khalid is the founder and CEO of Eva, a chatbot for consumer mortgages. Chatbots have been in the news a lot this year. First there was Tay, Microsoft's racist love child, who just couldn't keep herself under control. Then came Facebook with its Messenger bots, which, by most accounts, didn't start well. And now there's news coming from Viv, which at first glance seems like Siri 2.0.